Cable telegraphy



.Fune 23, 1925i 1,5438% F. QQNNEIRY CABLE TELEGHAPHY Filed April 17 1924 ZSheet=-Sheet l INVENTOR (v Alder ECO/mar ATTORNEY? I high electrostatic capacity Patented s 23, 1925.

- uurrao STATES nmma r. commas, or JAMBSA, vonx.

oruaw voax, u. 2., A

. MERCIAL CABLE COMFANY,

assrcuoa or nun-1mmro was conconrona'rmn or new 1031:.

cnsniz rns'enarnv.

Application ma April 11;"ie24. Serial in. 101,154.

To all whom it may 1 concern: I

Be it known that I, ALDER F. Com'vnnv, a subject of the King of Great Britain, and a resident of J amaica, in the co'unty of Queens and State of New York, have invented certain new and useful Improvements in Cable Telegraphy, of which the following is a specification.

In my application for patent, Serial No. 667 ,056, filed October 6, 1923, I have described a regenerative vibratory repeater for telegraph circuits. The apparatus there, in described may submarine cables and will repeat in perfect form positive and negative signals. It will not,'however, repeat zero signals.

The usual practice on submarine cables of is to use positive, negative and zero current values in the transmission of signals. When it is desired to repeat automatically the signals from 'one cable section into another the received signals operate a moving coil relay. The moving coil relay in turn controls transmitting relays which relays in turn control the cur-- rents applied to the next section of cable. The repeated signals are not as a rule as perfectl original y transmitted- Defects in the ad- 'ustment of the apparatus or imperfections in the duplex balance may cause the repeated signals to be improperly formed.

The main object of my invention is to provide a regenerative vibratory repeater capable of dealing with positive, negative and zero signals and to provide means whereby said repeater will vibrate in synchronism with the signals as sent. out by the transmitting apparatus. The repeated signals from the repeater herein described will be perfect in form even though the signals were received in considerably distorted condition. a

Another important object of the invention is to provide means whereby the received signals will operate themcans for maintaining the repeater in synchronism -with the signals transmitted from the sending apparatus.

In the drawings,

Figure l is a diagrammatic View of an apparatus for carrying out the invention and includes receiving apparatus and a regenerative rebe used in connection with formed as the signals which werea moving coil relay of a cable.

peater 'set operated from the-moving coil relay; V a

Fig. 2 a diagrammatic view showing graphically the regenerative action of the regpater; an

i 3 a diagrammatic grap ically the vibrating element and the signal units. Referring to Fig. 1, MGR designates a moving coil receiving relay. It is assumed that this relay will be actuated in the usual manner by the signals received over a cable, the signals originally being transmitted by an automatic cable transmitter of any approvedv and-usual form. A positive current will cause the tongue of relay MGR to touch its contact Sand a negative current. will cause its tongue to touch contact M. Zero or no current will cause the tongue to remain in a central position engaging with neither contact.

view illustrating the synchronous movement of In Fig. 1, LCR designates a line-control differential windings, the curved lines A to B representing one winding and the curved lines C to D. representing the other wind:

ing. Each relay is provided with a'tongue T actuated by the armature and with a spacing contact '3 and a marking contact M. A current flowing from A to B or from C to D will cause the tongue T to make contact with stop S, while a current flowing from B to A or from D to C will cause the tongue T to make contact with sto M. Relays LCR, SR, CR, PTR, MTR s ould be centered so that with no current flowing through the windings their tongues will clin to either contact. when so placed. Relays LR and MLR should be given a magnetic bias so that the normal position of their tongues will be on stop S.

TF designates a vibrating element in the form of a tuning fork. This forkis electrically driven by means'of a driving magnet DM and driving contact 0". -It is caused to vibrate in the manner of a common hell or buzzer. This form of device is well known and need not be more particularly described herein. Change in the natural riotl of vibration of the tuning fork may 8: made by adjusting the movable weights MW to different positions on thtines' of the tuning fork. CM designates a corrector magnet which acts magneticall uponthe J'suning fork. A currentthroug the windings of magnet GM will reduce the amplitude of vibration of the tuning fork and thereby increase the frequency, of current through the corrector-magnet is controlled b the corrector-reliiy. The how of current tirough magnet Chis intermit tent and occurs at irregular intervals and serves to maintain the tuning fork in jsynchronism with the recived'signals as will be fully hereinafter, described.

tween and engages coyrrector contacts {C and Ci The other'ftme of engages with, simultaneously, selecting contacts C and C It is necessarydthat the tuning fork TF vibrate in synchronism with the received signal units, For each unit length of. sig

7 nal received over the cable the tuning fork must make one complete cycle of vibration. e means for maintaining the tuning fork vibratin in synchronism with the line si%i2als is as allows:

i he tuning fork must means of the movable wei hts M'W until it will make slightly less an a com lete cycle of vibration for each unit lengt of received signal when there is no current flowing through the corrector magnet. The corrector magnet when energized must exert a magnetic efiect on .the'tuning fork sufiicient to cause the frequency of vibration to be increased so that the tuning-fork will make slightly more than a complete-cycle of vibration for each unit length of received signal. The result'of this arrangement is that when the corrector'magnet CM is not energized the tuning fork will vibrate at too lowa frequency and when the corrector magnet is'energized the tuning fork will vibrate at too high a frequency. An automatically operating correction means causes the corrector magnet OM 'to'become decaergized when the frequency of'the tuning fork gets ahead-of the received signal units, and a. so causes the corrector magnet to becomeenergized when-;-the frequency of the tuning fork falls behind the frequency of the line signal units." This automatic correction is accomplished by means controlled 4 and operated by the signal impulses re ceived over the cable, as he after described.

The tongue '1 of themovmg-eoll receiving relay MGR is connected to thejwindings of relays LGR, PLR MLR. The linecontrolrelay LCR is glven a neutral-adjustment so that, with no current through its tongue of relay the tuning fork 'ing contact with G.

first be adjusted. by

j lay 0R willrest indiiferently gages with stop M the tongue of relay LCR will ,move to contact M. I ,now, the tongue of relay MGR should move to a central nosition and engage with neither contact there will be no current through the windings of relay LCR but the tongue of rclay LCR will continue to make contact with its contact M.

It will thus be seen thatthe tongue of relay LCR will move or tend to move when the MGR engages with either contact" Sior M but will not move when the A ton e of relay-jMQR is in a central position. One tine of the tuning fork vibratcsibe etongue of relay LCR is" connected to; the Windingsof relaySR and thence to ground through contact C? and the tuning fork. Therefore, thereIayfSR will be under the influence of the tongue of the relay Lilli; 0211; when the Another circuitfrom the tongue T of the relay LCB goes through fixed condenser FC totongue T of relay SE. The stop S of relay SR is connected to thewindin the stop M o winding D to C of the correcto'r relay CR, so that the circuit from ten ue SR will be through one'o the windings of relay CR and thence to ground, through contact (3 and the tuning fork. Any current impulse from condenser FC must pass through either one or theother winding of relay CR and the position of the tongue of rela 'SR determines which windin of relay LR the condenser impulse wil .go through. When the tunin fork is making connection with contact a positiveimpulse on terminal A or a negative impulse on terminal D of relay CR will'throw the tongue'of that relay" to the left, but a negro- 'tive impulse on' FC will throw the tongue of relay CR to the left. Assuming the tuning fork is makn contact with C when the tongue of 6B moves from right to left, that is from M to S, the tongue of relay SR will remain 'on'its' stop the condenser SC ings G to D of CR; and the tongue'of rewill move to the left to sto S. W'hen,' however,- the tongue moves from left to right, from stop S to stop M, the tongue of relay SR will remain on its stop S, and condenser will flow PA'to B of :relay CR. and relay SR is connected to f T of relay of relay GR- tuning fork is mik- M and the impulse from will flow through windthe impulse fromthe through windings vA to B of relay CR and the tongue of said CR will be moved or tend to move S. When the tongue of relay LOR- moves from right toleft or from left to right at the moment that the tuning fork is making contact with C, then tongue T of relay CR will be thrown to the right due to the condenser impulse from FC just as soon as the fork makes contact with C". The impulse from the condenser can only take place when the fork is making contact with C, and the tongue of relay SR to stop -moves only when the fork makes contact with C It should be noted that each time tongue T of relay LCR movesv from one contact to the other a short impulse from condenser FO will pass through one of the windings of rela- GR. If this movement of the tongue 0 relay LCR should occur when the tuning fork is touching contact C then the condenser discharge will immediately occur, and as tongue T of relay SR will not move because the tuningfork is not touching contact C? the tongue of relay CR will be thrown to stop by the com denser discharge. If, however, this movement of tongue T of relay LCR should occur when the tuning'fork is touching con-.

tact C the discharge from condenser FC through relay CR will be delayed until the tuning fork touches contact 0*, but this movement of. tongue T of relay LOB occurring when the tuning fork is making contact with C will cause movement of tongue T of relay SR, and the condenserdischarge which occurs when the tuning fork touches contact C will throw the tongue T of relay CR to the stop M. I I

It will be evident from the foregoing that for each movement of-the tongue of LCR there will be a discharge from condenser and if this movement of the relay LCR occurs when the tuning fork is touching contact C the tongue of the switch relay .SR will move, so that the condenser dis.- char throws the tongue of corrector re- R to stop M, if this movement la of? the tongue of the relay LCR should occur when the'tuning fork is touching C the switch relay SB- will 'not be operate and the condenser discharge will throw the tongue of the corrector relay OR to stop, S.

The relay SR acts as a switch relay and switches the condenser discharge through either one or the other of the windingsof the relay CR. If the'tongue of the relay LCR moves when the tuning fork is touching one of its contacts the relay SR will move and'switch the condenser impulse through relay CR so its t on'gu t will move in a certain direction. If on tongue of the relay LCR moves when the tuning fork is touching the other contact the relay SR will fail to move and the condenser imthe corrector magnet pulse will move the tongue of relay OR in the other direction;

When the'tongue of corrector relay CR makes contact with M the corrector magnet GM will be energized and the period of vibration of the tuning fork will increase. When the. tongue of corrector relay CB leaves contact M, no current will flow through corrector magnet CM and the frequency of'vibration of the tuning fork will decrease. I

The tongue of the plus locking relay PLR is connected. through its own winding D to C to the terminal D of the winding D to' C of the plus transmitting relay PTR, the

terminal C of said winding heing'oonnect- I to the contact 0 of the tuning terminal C of said win ingbetheir contacts vS.

The relays may be magnetically biased to secure this condition.

The operation of follows:

The period of vibration of the tuning fork is set by means of the movable weights MW so that it makes slightly less than a complete cycle of vibration for each unit length of received signal when no current flows through the corrector magnet CM, and makes slightly more than a com lete cycle of vibration for each unit lengt of received signal when current flows through CM. As hereinbefore pointed out the movement of the ton e of the receiving moving coil relay MO will be controlled by signal impulses of positive, negative or zero currentvalue. Assuming nodistortion mission the tongue the apparatus is as T of relay MGR will make contact with its stopsS and Mat unit (l LCR is controlled by relay MGR. If the of the signals in transvibration of the tuning fork is in suchrelation with the movements of the I of the relay LCR that they tuning fork is kin contact with stop C at the instant'that the tongue of therelay LCR moves to contact S or to the contact' M,

phase tongue then the tongue of the relay OR will be moved to its stop'S and the corrector mag-.

,net will be de-energized and the frequencyof the tuningyefork will be reduced.

tween the tongue of The phase relation the relayLCR and the tuning fork will now change and within a shortriod. of

time the tuning fork will be ma mg contact-with 'C at the instantthat the tongue of the relay. LCR makes'contact with its stop either S or M. The tongue of the Correctormelay CR will now he-moved to its stop M and the corrector magnet will be energized, whereby the frequency of vibration of the tuningiork will be increased. The tuning fork will be thus maintained in synchronismand inapproximate. hase reby the transmitting station and, therefore:

the tongue of relay LCR does not move at exactly unit or multiple unit intervals, there will be a speeding up and slowing down of thefrequency of vibration of the tuning'fork, but since the speeding up and slowing down effect on the tuning fork due to corrector magnetCM is quite small and must ersist for a considerable time before the vibration of the tuning fork can get far out of relative phase relation with the received signals, th'is'system of' holding the tunin fork in step with the received cable signal; is very effective. even though the,

received cable signals are considerably distorted. I

When the correcting system is vholdin the tuning fork in step with the receiv unit signal len ths it will be noted that the tunin fork will make OQ-Iitafit with o and C simultaneously, once for each unit length of received signal. 1

The circuit from the tongue of relay MGR oes through the winding of relay LCR, t irouh one winding of relay PLR from A to and thence through one winding of relay MLR from B to A. -As previously explained, if the tongue of relay MGR is in a central PLR and MLR will rest on their contacts S. If the tongue of relay MGR makes contact with stop S, the tongue of relay PLR will move to, contact M. Thetongue of :relay MLR will remain on stop s. If, however, the tongue of relay MGR makes con tact with stop M, the tongue of relay MLR will move to contact M, while the tongue of relay PLR will be on stop S.

- Each time the. tuning forkmakes contact -with C and C one circuit-will be comlpleted from the tongue ing T of relay through its own win and through one winding of relay PTR to the tuning fork,

' and another circuit from-the tongue T of relay MLR through its own' winding and through one winding of relay MTR to the tuning forln" The current through the 50 position the tongues of relaysto C windings of relays PLB and MLB is of greater value than the currents through the other windings and the direction of the current is such that it tends to hold the tongues of those relays to whichever contact they may be touching. When the tuning fork is not touching contact C and the relays PLR and MLR will be under the influence of the relay MGR. When the tuning fork engages with contacts C and C the tongues of relays PLR and MLB will be locked up and the current through'the D. to (l. windings of relays PTR and MTR will cause the tongue of relay PTR to as- \sumii 'the position of the tongue of relay PLR, and also cause the tongue of. relay MIRR tosassume the position of the tongue of -I'e lay MLR. This method of locking up thetongues of relays PLB and MLR insures that there will be no movement of the tongues of relays PLB and MLB during the time that the plussand minus transmitting relays PTR and M'lR are connected to them, and the tongues of relays PTR and MTR will move only at unit time intervals, the instant that they move being defined by the moment of contact of the tuning fork with C and C The contacts and tongues of relays PIIR and MTR are connected to the cable batflowing through the D to C windings of relays PTR and MTR andany jar or vibra-' tion might cause their tongues to break connection with their contacts. Resistances P and P are bridged across the battery CB and,from the neutral point of this potentiometer, circuits lead to theB terminalswf relays PTR and MTR and thence to their respective tongues. The small current in these circuits flows through the B to A windings of relays PTR and MTR- in such direcq tion as to hold their tongues firmly to whichlever contact they are touching. This current is of small value and does not interfere withthe normal operation of the relays but I merely insures that the relays make firm contact during the time there is no current through their operating windings Dto C.

It is understood thatthe apparatus herein describedwill correct any distortionin signals that is less than'one-h'alf a unit. If the distortionof the; greater than one-half aun'it-period so 'Ith'at eas s signal isi ting apparatus to transmit signals of posiapparatus and the transmitting apparatus the signal impulse will be maintained. be-

fork with C and C foperation of the signal,

i relay will persist for a full unit period until the uel unit sent out t rough the transmitting relays will fork and its contacts C and C.

respect to has proven that plication and it may be vrials, on land lines or other signalling sysmultiple-unit length said means being interuaaeo I paratus adapted to be ceived signal impulses, two transmitting relays, means whereby the signal receiving apparatus will cause the two transmitting relays to transmit signals of unit 0r multiple-unit length said means being interposed between and in circuit with the receiving apparatus and the transmitting apparatus, and means whereby the signal receiving apparatus will cause the two transmitting relays to transmit signals of positive, negative or zero current value in response to received signals of corresponding current value said means being interposed between and in circuit with the receiving apparatus and the transmitting apparatus.

3. A cable telegraph repeater system wherein the signals received and transmitted are of unit or multiple-unit length of positive, negative or zero current value, a signa freceiving apparatus adapted to be operated by the received signal impulses, a signal transmitting apparatus, a vibrating element, means whereby the signal receiving apparatus and the vibrating element will cause the transmitting apparatus to transmit signals of unit or multiple-unit length said means being interposed between and in circuit with the receiving apparatus and the transmitting apparatus, and means whereby the signal receiving apparatus will cause the transmitting apparatus to transmit signals of positive, negative or zero current value in response to received signals of corresponding current value said means being interposed between and in circuit with the yond the moment of contact of the tuning which, in the normal should show a ange in the-position of the tongue of the MGR and the tongues of relays PLB and M1111, then the distortion in the signal next contact or the tuning fork with C and C. The moment of contact of the tuning fork with contacts 0 and 0 marks the sigriods so that the signal impulses be defined by the vibration of the tuning No adjustable means is provided to insure that'the tuning fork will make contact with C and G at, the proper moment with the received signals, for experience this adjustable means is unnecessary on-a repeater of this type.

The 'correction of the distortion of the signals is accomplished by the tuning fork through its cooperation with the relays PLR nd MLB and with the transmitting relays lTB and MTR. To bring-about this correction of the distortion in the signals it is only necessary that the tuning fork shall vibrate in synchronismwith the incoming sigpils of unit length.

. nile the largest application of this rebe on submarine cables limited to that apused to repeat sigater will probably its use is by no means terns where a signalling code having pos1- tive, negative and zero current intervals is used; and it me also be used to repeat sig nals from a lan line into a sumbarme cable and vice-versa.

, -What I claim is: v

1. A cable telegraph repeater system wherein the signals received and transmitted are of positive, negative or zero current value, comprisinga signal receiving apparatus adapted to be operat d by the received signal impulses, a signa transmitting aparatus, means whereby the signal receivmg apparatus will cause. the transmitting apparatus'to transmit signals of unit or apparatus, transmitted by the transmitting apparatus being controlled by the signal receiving apparatus and the vibrating element.

4, A cable telegraph system wherein the signals transmitted are of unit length or multiple unit length of positive, negative or zero current value, comprising a signal receiving apparatus, two transmitting relays, a vibrating element, means whereby the signal receiving apparatus-(and the v1- brating element will cause "the two transmitt-lug relays to transmit signals of unit v or multiple unit length, and means whereby the signal receiving apparatus willcause the two transmitting relays of positive, negative or zero current value in response to received signals of corresponding current value, the unit length of t e signals transmitted by the said two reposed between and incircuit with the receiving apparatus and the transmitting apparatus, and means whereby the signal receiving apparatus will cause the transmit tive, negative or zero current value in response to received signals of corresponding current value said means bein interposed ing apparatus and the vibrating element.

between and in circuit with t e receiving 5. cable telegra h system wherein the signals transmitte are of unit or mul- 2. A cable telegraph repeater system tiple unit length of positive, negative 'for wherein the signalsreceived andtransmittedzero current value, comprising are of positive, negative or zero current ceiving .apparatus, a signal value, comprising a signal receiving apapparatus, 8.

operated by the reto transmit signals receiving apparatus and the transmitting the unit length of 'the signals lays being controlled by. the signal receiv-v v 7 whereby the signal receiving apparatus and the vibrating element will cause the transmitting apparatus. to transmit signals of unit or multiple unit length, means whereby the signal receiving apparatus will cause the transmitting apparatus to transmit sig: nals of positive,

,value in response to received signals of corresponding current value, the unit length of the signals transmitted by the transmit ting apparatus being controlled by the sig nal receiving apparatus and the vibrating element, and means for maintaining the vibrating element in] synchronismwith the 7 units of the received signals.

6. A. cable telegraph system wherein the signals transmitted are of unit length or multipleunit length of positive, negative or zero current value, comprising a signal receiving apparatus, two transmitting relays, a vibrating element, means whereb the signal receivingapparatus and the v1- brating element will cause the two transmitting relays to transmit signals of unit or multiple. unit length,- means whereby the signal receiving apparatus will cause the two transmitting relays to transmit signals of positive, negative or zero current value in response to received signals of corresponding current value, the unit length of the signals transmitted by the said two relays being controlled by the signal receiving apparatus and the'vibrating element, and means for maintaining the vibrating element in synchronism with the units of the received signals.

7. A cable telegraph s stemwherein the signals transmitted are 0 positive, negative or zero current Value, comprising a signal receiving apparatus, two transmitting relays, a vibrating element, means. whereby the signal receiving apparatus and the vibrating element will cause the two transmitting relays to transmit signals, means whereby the signal receiving apparatus will cause the two transmitting relays to trans.

mit signals of positive, negative or zero current value in response to received signals of corresponding current value, the length of .the signals transmitted are of positive, nega-' tive or zero current value, comprising a receiving relay to receive the signals transmitted from the distant transmitting station, a line control relay operated by the receiving relay, a vibrating tuning fork haying two arms, one arm vibrating between two 'nected to the.-'out-go1n negative or zero current having a magnetic bias tohold relay and to" receiving relay,-

contacts (I -C, the other arm vibrating be tween contact C and two contacts (l C adriving magnet for the tuning fork having its coil electrically connected to contact 0 two transmitting relays electrically concircuit, one of said relays transmitting p us current impulses and the other transmitting minus current impulses, sindboth ofsaid. relays operating to connect theout-goingcircuit' to ground whenthe recei'ving relay tongue is inneu:

tral or zero position, a plus lockin electrically conncted transmitting relay, electrically connected to" one coil of the minus transmitting relay relay 'toone coilof the plus a minus locking relay 80 the plus locking 5 relay and the minus locking relay being electricall connected to-the line control relay wherel) coils of the line controltongues' of the i locking. relays in opposite directions the tongues of one of their stops when'the receivin is in neutral or .zero position, a switc having its coils relay relay of the switch relay and vto the contact a cor-rector magnet arranged to operate on line control re lay and the switch relay, electrical connections between the coils ofthe y impulses of current" through the relay will move the.

the-locking relays them against i a connecuul to the line control; the contact C, a corrector I relay having its coils connected to the sto( ps 1 the vibratingelement and controlle'dlby' the movements of the tongue of the corrector relay, anclectrical connection including a; fixed condenser betweenthe-tongues of the i v plus transmitting relay and the minus trans 4 mitting relay and the contacts (l fi fandj means whereby when the tongues of the locking relays are moved by their magnetic bias the plus and minus transmitting relays will placethe out-going circuit ground for zero signal impulses.

9. 'A regenerative vibratory repeater apparatus for cabletelegraph systems wherein the signals transmitted are of positive, negative. or. zero current value, comprising a receiving relay to receive the direct to signals transmitted from the distant transmitting Sta tion, a line control relay operated by the a. vibratingtuning fork, a driving magnet transmitting relayselectrically connected to the out-going circuit, one of said relays transmitting plus "current impulses and the other transmitting minus current impulses,

and bothof said relay's'operating to connect Q r the out-going circuit to ground when the receiving relay tongue is in neutral or zero position, a plus locking relay electrically connected to one coil of the plus transmits,

ting relay, a minus locking relay electrically connected to one coil of the minus tra'nsmit ting relay, the pluslocking relay and the; minus locking relay being electrically icon for the tuning' fork, two

at f.

' whereby when nected to the line control relay whereby impulses of current through the, coils of the line control relay will move the tongues of the locking'relays in opposite directions, the tongues of the locking relays having a magnetic bias to hold them against one of their stops when the receiving relay is in neutral or zero position, a switch relay having its coils connected to the line control relay, a corrector relay having its coils connected to the stops of the switch relay, a corrector magnet arranged to operate on the vibrating element'and controlled by the movements of the tongue of the corrector relay, an electrical connection including a condenser be tween the line-control relay and the switch relay, electrical connections between the coils of the plus transmitting relay and the minus transmitting relay and the contacts of the said tuning fork, means whereby when the tongues of the locking relays are moved by their magnetic bias the plus and minus transmitting relayswill place the out-going circuit direct to ground for zero signal impulses.-

10. A regenerative vibratory repeater apparatus for cable telegraph systems wherein the signals transmitted are of positive, negative or zero current value, comprising a re ceiving relay to receive the signals transmitted from the distant transmitting station, a line control relay operated by the re ceiving relay, a vibrating tuning fork, two transmitting relays electrically connected to the outgoing circuit, one of said relays transmitting plus current impulses and the other transmitting minus current impulses, and p both of said relays operating to connect the out-going circuit to ground when the receiving relay tongue is in neutral or zero posi-' t1on, a plus lock ng relay electrically con nected to one coil of the plus transmitting relay, a minus locking relay electrically connected to one coil of the minus transmitting relay, the plus locking relay and the minus locking relay being electrically connected to the line control relay whereby impulses of current through the coils of the line control relay will move the tongues of the locking relays in opposite directions, the

tongues of'the locking relays having a magnetic bias to'hold them against one of their stops when the receiving relay is in neutral or zero position, electrical connections between the coils of the plus transmitting relay and the minus transmitting relay, means the tongues of the locking relays are moved by their magnetic bias the "unit length.

plus. and minus transmitting relays will place the outoing circuit direct to ground for zero sign impulses, and means where y the line control relay and-the vibrating tuning fork will cause the transmittin I relays to transmit signals ofnnit or mu ip e 11. A regenerative vibratory repeater apparatus for cable telegraph systems wherein the. signals transmitted are of unit length or multiple unit length of positive, negative or zero current value, comprising a receiving relay to receive the signals transmitted 1 from the distant transmitting station, a line control relay operated by the receiving relay, a vibrating tuning fork, two transmitting relays electrically connected to the outgoing circuit, one of said relays transmitting plus current impulses and the other transmitting minus current impulses, and both of said relays operating to connect the outgoing circuit to ground'when the receiving relay tongue is in neutral or zero position, a plus locking relay one coil of the plus transmitting relay, a minus locking relay electrically connected to one coil of the minus transmitting relay, the plus locking relay and the minus locking relay being electrically connected to the line control relay whereby impulses of current through the coils of the line control relay will move the tongues of the locking relays in opposite directions, the tongues of the locking relays having a magnetic bias to hold them against one of their stops when the receiving relay is in neutral or zero position, electrical connections between the coils I of the lus transmitting relay and. the minus transmitting relay, means whereby when the tongues of the locking relays are moved by their magnetic bias the plus and minus transmitting relays will place the outoing electrically connected to circuit direct to ground for zero signa imulses, and means whereby the line control relay and the vibrating tuning fork will cause the transmitting relays to transmit signals of unit or multiple unit length.

12. A regenerative vibratory repeater apparatus for cabletelegraph s stems wherein the signals transmitted are o unit length or multiple unit length of positire,'negative or zero current value, comprising a receiving relay to receive the signals transmitted from the distant transmitting station, a vibrating tuning fork, two transmitting relays clectrically connected to the out-going circuit, one of said relays transmitting plus current v impulses and the other transmitting-minus current impulses, and both of said relays operating to connect the out-going circuit to groundwhen the receiving relay tongue is in neutral or zero position, a plus locking "plus transmitting relay, a minus'lockin 115-" .la electrically connected to one coil 0 the minus transmitting relay, the plus locking relay and the minus locking. relay being electrically controlled b the receiving relay whereby impulses o current through the coils of-the receiving relay will move the 1 ;ongues of: the locking reiays in op i'ctions,tthegongues of thej'lock ng relays posite dihaving a magnetic bias to hold them against one of their stops when the receiving. relay is inneutral or zero position, electrical eonnections between the coils of the plus trans-- relays will place the out-going eireuit dilel t to ground for zero signal impulses, and 1q means whereby the line control rela and the vibrating tuning fork will cause t e transmittin relays to transmit signals of unit or multip 0 unit len 'th. i

In testimony wli signature.

ALDER ECONNERY.

ereof I hereunto allix my It I 

